• Title/Summary/Keyword: Scale Factor Method

Search Result 1,018, Processing Time 0.03 seconds

Geotechnical Engineering Progress with the Incheon Bridge Project

  • Cho, Sung-Min
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2009.09a
    • /
    • pp.133-144
    • /
    • 2009
  • Incheon Bridge, 18.4 km long sea-crossing bridge, will be opened to the traffic in October 2009 and this will be the new landmark of the gearing up north-east Asia as well as the largest & longest bridge of Korea. Incheon Bridge is the integrated set of several special featured bridges including a magnificent cable-stayed girder bridge which has a main span of 800 m width to cross the navigation channel in and out of the Port of Incheon. Incheon Bridge is making an epoch of long-span bridge designs thanks to the fully application of the AASHTO LRFD (load & resistance factor design) to both the superstructures and the substructures. A state-of-the-art of the geotechnologies which were applied to the Incheon Bridge construction project is introduced. The most Large-diameter drilled shafts were penetrated into the bedrock to support the colossal superstructures. The bearing capacity and deformational characteristics of the foundations were verified through the world's largest static pile load test. 8 full-scale pilot piles were tested in both offshore site and onshore area prior to the commencement of constructions. Compressible load beyond 30,000 tonf pressed a single 3 m diameter foundation pile by means of bi-directional loading method including the Osterberg cell techniques. Detailed site investigation to characterize the subsurface properties had been carried out. Geotextile tubes, tied sheet pile walls, and trestles were utilized to overcome the very large tidal difference between ebb and flow at the foreshore site. 44 circular-cell type dolphins surround the piers near the navigation channel to protect the bridge against the collision with aberrant vessels. Each dolphin structure consists of the flat sheet piled wall and infilled aggregates to absorb the collision impact. Geo-centrifugal tests were performed to evaluate the behavior of the dolphin in the seabed and to verify the numerical model for the design. Rip-rap embankments on the seabed are expected to prevent the scouring of the foundation. Prefabricated vertical drains, sand compaction piles, deep cement mixings, horizontal natural-fiber drains, and other subsidiary methods were used to improve the soft ground for the site of abutments, toll plazas, and access roads. Light-weight backfill using EPS blocks helps to reduce the earth pressure behind the abutment on the soft ground. Some kinds of reinforced earth like as MSE using geosynthetics were utilized for the ring wall of the abutment. Soil steel bridges made of corrugated steel plates and engineered backfills were constructed for the open-cut tunnel and the culvert. Diverse experiences of advanced designs and constructions from the Incheon Bridge project have been propagated by relevant engineers and it is strongly expected that significant achievements in geotechnical engineering through this project will contribute to the national development of the longspan bridge technologies remarkably.

  • PDF

A study on Operation factors the Used automobile logistics complex using Fuzzy-AHP (Fuzzy-AHP를 활용한 인천항 중고자동차 물류단지 운영 성공요인에 대한 연구)

  • Kim, Byung-Hwa;Cha, Young-Doo;Ma, Hye-Min;Yeo, Gi-Tae
    • Journal of Digital Convergence
    • /
    • v.15 no.7
    • /
    • pp.97-109
    • /
    • 2017
  • Domestic vehicle penetration rate is growing at 3% per year, but consumers are increasingly buying used cars due to steady price hikes Nevertheless, the used car export market is expected to decline due to import regulations of major countries and the low grade environment of Used car export complex. Therefore, this study using Fuzzy-AHP was aimed to find operational factors of Used car logistics complex and establish a practical management plan of Used car logistic complex in incheon port. Fuzzy-AHP is the method that can be calculated weight of multi-level criteria and change linguistic ambiguity of human to Fuzzy Number. So it's able to propose the realistic decision making alternatives. As a result of the literacture reviews, present study focused on the analysis of the present situation of the logistics of the used car and the activation of the complex, suggested the activation plan and activation of the logistics complex. In the analysis of operational factors, logistic complex cost factors were found to be the most important factors by recording the weighted value of 0.306 in the above factors. The detailed factors were as follows: rent, accessibility, and logistics site size. It is necessary to compute competitive rent for the highly-advanced used car logistics complex, and to realize the rental support policy and to consider designating the free trade zone. In addition, it is necessary to expand the access infrastructure and secure the scale of the company for overseas buyers, and it is necessary to improve the overall government laws and introduce IT system for the future.

The effect of orthodontic treatment and orthodontic treatment effect on dental hygiene students Factor (치위생과 학생의 교정치료 실태와 교정치료 효과에 영향을 미치는 요인)

  • Shin, Myong Suk;Hwang, Ji-Min
    • The Journal of the Convergence on Culture Technology
    • /
    • v.4 no.1
    • /
    • pp.57-65
    • /
    • 2018
  • The purpose of this study was to investigate the factors affecting the actual condition and effectiveness of orthodontic treatment among some dental hygienists and students. This study was carried out from September to December, 2016 to describe the purpose of the study and the method of writing the questionnaire for some dental hygienists and students. The final 430 sections were analyzed and analyzed using PASW Statistics 18.0. First, the duration of orthodontic treatment was 34.4% for college students, 36.9% for orthodontic treatment for less than 2 ~ 3 years, and 62.3% for internal motivation. The factors affecting the orthodontic treatment effect were the patient's cooperativeness and the hospital's scale was the lowest. The higher the grade level, the more the clinical experience and dental part-time experience were, the higher the correlation between dental specialty and dental hygienist's medical service, education and counseling was .521(P<0.001). The higher the level of cooperation, the higher the grade level, the more dental treatment and orthodontic treatment experience, the lower the level of family co - operation. Therefore, it is important to emphasize the importance of cooperation of orthodontic patients and to develop a strategic program for each individual patient.

Factors Associated with Burnout of Korean Child Protective Service Workers (아동학대예방센터 상담원의 소진관련 요인에 관한 연구)

  • Yoon, Hye-Mee;Park, Byung-Kum
    • Korean Journal of Social Welfare
    • /
    • v.56 no.3
    • /
    • pp.279-301
    • /
    • 2004
  • Relations of factors associated with burnout were investigated among 124 child protective service workers currently working in Korean Child Abuse Prevention Centers nationwide. Three categories of factors associated with burnout were examined; (1) individual characteristics, (2) job-related characteristics, and (3) job-satisfaction. Social survey method using questionnaires by mail was employed. MBI(Maslach Burnout Inventory) for measuring burnout, a part of Smith, Kendal & Hulin's JDI(Job Description Index) for job-satisfaction, and a scale measuring the special characteristics of job developed by researchers were used. Mann-Whitney test and Kruskal-Wallis test were employed to analyze the data. Across all burnout sub-scales(emotional depletion, dehumanization of clients, lack of feelings of achievement), subjects reported a high degree(above the cutting point) of burnout. Several factors were identified as associated with burnout. Child protective service workers who are young, single with front line worker status reported higher burnout. Lack of education and training before the job location were another factors which contributed to worker burnout. Lack of proper supervision stood out as another burnout provoking factor. Job-satisfaction was negatively correlated with all three burnout sub-scales, which meant the lower the job-satisfaction, the higher the burnout of service workers. The findings implicate that the administrators of Child Abuse Prevention Centers should pay close attention to their workers' sign of burnout and develop carefully designed support system which include provision of excellent supervision, proper education and training opportunities and organizational effort to strengthen employees' overall job-satisfaction to secure their quality of services toward abused children and their family.

  • PDF

Effect of Rhythmic Exercise Program to Elderly on Risk Factors of Fall Injury (노인을 대상으로 한 율동 운동 프로그램 실시 효과: 낙상 위험 요인과 관련하여)

  • Lee, In-Sook;Chin, Young-Ran;Lee, Dong-Ok;Kim, Yun-A;Baek, Kyeng-Ae
    • Research in Community and Public Health Nursing
    • /
    • v.12 no.3
    • /
    • pp.600-608
    • /
    • 2001
  • Accidents are the fourth-leading causal factor of death among the elderly, and fall is a major type of accident (53.17%). Many cases of falls in the elderly result in delayed discovery and loss of quality of life. As the number of the elderly grows, falls will be a more important health problem. Most previous research on falls investigated prevalence. mortality, and the related factors. There are many studies proving the effect of rhythmic movements. But few researches considered linking risk factors of fall with rhythmic movements. Purpose: We want to show the changes after performing rhythmic movement program, in risk factors of falls and mobility such as flexibility, balance, muscle power and persistency in the elderly, in order to provide basic information needed for the development of fall injury prevention program for the elderly. Method: The design of this study is quasi-experimental, the equivalent control group, pretest-posttest. The subjects consist of 124 people who lived in Do-Bong-Qu. Seoul, agreed to participate in this study, and were able to follow this rhythmic movement program. About 93 % of them are from 65 to 84 years (Mean${\pm}$sd: $73.7{\pm}5.7$): 64% are female. The rhythmic movement program was designed. and performed by two community health nurses working in the Do-Bong-Gu Public Health Center, regularly twice a week from May, 4 to December, 17. in 10 senior citizens' community centers. Risk factors of fall were measured with RAFS- II (Risk Assessment for Falls Scale II) by asking about each item: mobility was measured by observing their specific movements asked by investigators. Results: 1. After performing the program during 7 months, risk factors score of falls were decreased significantly (paired-t = 4.77. p<0.01). 2. After performing the program during 7 months, flexibility (paired-t = 2.26. p=0.03) and mobility were improved (paired-t = 4.98. p<0.01). but muscle power and persistency did not change (paired-t = 0.33. p=0.74). Overall, mobility affecting the occurrence of falls was improved significantly (paired-t = 5.15. p<0.01). Conclusions: A regular rhythmic movement program can be helpful in preventing falls in the elderly. Further. we can develop a fall injury prevention program using rhythmic movement.

  • PDF

Analysis of Soil Erosion and Sediment Yields at the Doam-dam Watershed considering Soil Properties from the Soil Reconditioned Agricultural Fields using SATEEC System (SATEEC 시스템을 이용한 객토 토양의 토성고려에 따른 도암댐 유역의 토양유실 및 유사량 분석)

  • Yoo, Dongsun;Ahn, Jaehun;Yoon, Jongsuk;Heo, Sunggu;Park, Younshik;Kim, Jonggun;Lim, Kyoung Jae;Kim, Ki-sung
    • Journal of Korean Society on Water Environment
    • /
    • v.23 no.4
    • /
    • pp.518-526
    • /
    • 2007
  • There have been serious soil erosion and water pollution problems caused by highland agriculture practices at Doam-dam watershed. Especially agricultural activities, chemical and organic fertilizer and pesticide applications, soil reconditioning to maintain soil fertility are known as primary causes of soil erosion and water qaulity degradation in the receiving water bodies. Among these, soil reconditioning can accelerate soil erosion rates. To develop soil erosion prevention practices, it is necessary to estimate the soil erosion from the watershed. Thus, the Universal Soil Loss Equation (USLE) model has been developed and utilized to assess soil erosion. However, the USLE model cannot be used at watershed scale because it does not consider sediment delivery ratio (SDR) for watershed application. For this reason, the Sediment Assessment Tool for Effective Erosion Control (SA TEEC) was developed to assess the sediment yield at any point in the watershed. The USLE-based SA TEEC system can estimate the SDR using area-based SDR and slope-based SDR module. In this study, the SATEEC system was used to estimate soil erosion and sediment yield at the Doam-dam watershed using the soil properties from reconditioned agricultural fields. Based on the soil sampling and analysis, the US LE K factor was calculated and used in the SA TEEC system to analyze the possible errors of previous USLE application studies using soil properties from the digital soil map, and compared with that using soil properties obtained in this study. The estimated soil erosion at the Doam-dam watershed without using soil properties obtained in the soil sampling and analysis is 1,791,400 ton/year (123 ton/ha/year), while the soil erosion amount is 2,429,900 ton/year (166.8 ton/ha/year) with the use of soil properties from the soil sampling and analysis. There is 35 % increase in estimated soil erosion and sediment yield with the use of soil properties from soil reconditioned agricultural fields. Since significant amount of soil erosion are known to be occurring from the agricultural fields, the soil erosion and sediment yield from only agricultural fields was assessed. The soil erosion rate is 45.9 ton/ha/year without considering soil properties from soil reconditioned agricultural fields, while 105.3 ton/ha/year after considering soil properties obtained in this study, increased in 129%. This study shows that it is very important to use correct soil properties to assess soil erosion and sediment yield simulation. It is recommended that further studies are needed to develop environment friendly soil reconditioning method should be developed and implemented to decrease the speed of soil erosion rates and water quality degradation.

An influence on some university students' drinking quality and the plan for cutting down on drinking (일부 대학생들의 음주량에 미치는 영향과 절주방안)

  • Kim, Seung-Dae;Kim, Myung-Gwan
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.17 no.9
    • /
    • pp.221-227
    • /
    • 2016
  • The purpose of this study is to investigate the effect of social factors and social stress with respect to alcohol consumption for university students and to provide basic data in efforts to develop educational method that teaches how to decrease alcohol consumption and deny demanding drinking. Questions concerning typical features and social stress from drinking were revised through 300 university students' self-recording surveys between April 8 and 9 in 2015. It consisted of 10 questions using a 4-point Likert scale. Moreover, the reliability of tool was Cronbach ${\alpha}=.82$. We used SPSS 18.0 and conducted frequency, ${\chi}^2$ and path analysis. If the frequency of drinking (B=.206, p<.001) gets low and the social stress from drinking is low (B=-.397, p<.001), the amount of drinking increases, particularly for men more than women (B=.169, p<.05). For women more than men (B=.274, p<.01), if monthly income is high (B=.178, p<.05) and stress from drinking is low (B=-.349, p<.01), the frequency of drinking is high. If the culture of practice in drinking has not formed voluntarily through education or publication, legal restriction that increases the cost of drinking has to be established, like smoking, to reduce the volume of drinking and promote moderation in drinking. The publication and education that teaches drinking leads to bad situations have to be conducted, much like the education programs involved for smoking. Also, discrimination of non-drinker has to be removed with the change of culture to reduce the stress by drinking.

Herding Behavior of the Seoul Apartment Market (서울시 아파트시장의 군집행동 분석)

  • Kim, Jung Sun;Yu, Jung Suk
    • Korea Real Estate Review
    • /
    • v.28 no.1
    • /
    • pp.91-104
    • /
    • 2018
  • In this study, the occurrence and degree of herding behavior as a market participant behavior in a housing market were analyzed. For the analysis method, the actual sales price was applied in the CSAD (Cross-sectional Absolute Deviation) model, which has been used the most of late for herding behavior analysis. For the analysis contents, these were subdivided into region, elapsed year, size, and market condition to analyze the regionality and the internal and external factors. For the study results, first, there was no herding behavior in the entire region of Seoul. By region, herding behavior occurred in the downtown, southeast, and northwest regions, which coincided with the results of the precedent study (Ngene et al., 2017). Second, in the market analysis by elapsed year, herding behavior was captured in dilapidated dwellings. By size, herding behavior was observed in small-scale ($60m^2$ or less) apartments and in $85m^2$ or higher and less than $102m^2$ national housing units. Third, during the time of the global financial crisis, herding behavior was not observed in all the regions, whereas when the market situations were in a boom cycle, it was observed in the northwest region. These results suggest that there is a difference from the stock market, where in a period of recession, herding behavior occurs intensively with the expanding fear of incurring losses. This study is significant in that it analyzed the market participant behaviors in the behavioral economic aspects to better understand the abnormal phenomenon in a housing market, and in that it additionally provides a psychological factor - market participant behavior - in market analysis.

Landslide Susceptibility Assessment Using TPI-Slope Combination (TPI와 경사도 조합을 이용한 산사태 위험도 평가)

  • Lee, Han Na;Kim, Gihong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.36 no.6
    • /
    • pp.507-514
    • /
    • 2018
  • TSI (TPI-Slope Index) which is the combination of TPI (Topographic Position Index) and slope was newly proposed for landslide and applied to a landslide susceptibility model. To do this, we first compared the TPIs with various scale factors and found that TPI350 was the best fit for the study area. TPI350 was combined with slope to create TSI. TSI was evaluated using logistic regression. The evaluation showed that TSI can be used as a landslide factor. Then a logistic regression model was developed to assess the landslide susceptibility by adding other topographic factors, geological factors, and forestial factors. For this, landslide-related factors that can be extracted from DEM (Digital Elevation Model), soil map, and forest type map were collected. We checked these factors and excluded those that were highly correlated with other factors or not significant. After these processes, 8 factors of TSI, elevation, slope length, slope aspect, effective soil depth, tree age, tree density, and tree type were selected to be entered into the regression analysis as independent variables. Three models through three variable selection methods of forward selection, backward elimination, and enter method were built and evaluated. Selected variables in the three models were slightly different, but in common, effective soil depth, tree density, and TSI was most significant.

Radiation Flux Impact in High Density Residential Areas - A Case Study from Jungnang area, Seoul - (고밀도 주거지역에서의 복사플럭스 영향 연구 - 서울시 중랑구 지역을 대상으로 -)

  • YI, Chae-Yeon;KWON, Hyuk-Gi;Lindberg, Fredrik
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.21 no.4
    • /
    • pp.26-49
    • /
    • 2018
  • The purpose of this study was to verify the reliability of the solar radiation model and discuss its applicability to the urban area of Seoul for summer heat stress mitigation. We extended the study area closer to the city scale and enhanced the spatial resolution sufficiently to determine pedestrian-level urban radiance. The domain was a $4km^2$ residential area with high-rise building sites. Radiance modelling (SOLWEIG) was performed with LiDAR (Light Detection and Ranging)-based detailed geomorphological land cover shape. The radiance model was evaluated using surface energy balance (SEB) observations. The model showed the highest accuracy on a clear day in summer. When the mean radiation temperature (MRT) was simulated, the highest value was for a low-rise building area and road surface with a low shadow effect. On the other hand, for high-rise buildings and vegetated areas, the effect of shadows was large and showed a relatively low value of mean radiation temperature. The method proposed in this study exhibits high reliability for the management of heat stress in urban areas at pedestrian height. It is applicable for many urban micro-climate management functions related to natural and artificial urban settings; for example, when a new urban infrastructure is planned.